<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./vue.js"></script>
</head>

<body>
    <div id ="app">
        <my-button></my-button>
    </div>
    <div id ="app2">
        <my-button></my-button>
    </div>
    <div id ="app3">
        <my-button></my-button>
    </div>
    <script>
    Vue.component('myButton', {
        template: `<button @click="count += 1">{{count}}</button>`,
        data() {
            return {
                count:0
            }
        }
    })
     var app = new Vue({
        el: '#app',
     });

     var app2 = new Vue({
         el: '#app2'
     });
     
     var app3 = new Vue({
         el: '#app3'
     })
    </script>
</body>

</html>